Machine for chamfering gears



March 1944- c. T. GALLOWAY MACHINE FOR CHAMFERING GEARS '7 Sheets-Sheet1 Filed March 16, 1940 CLARE/V65 7? GALmM/AY H mflome March 7, 1944. c."r. GALLOWAY v MACHINE FOR CHAMFERING GEARS Filed March 16. 1940 '7Sheets-Sheet 2 Bnvcmor Z Claw/v05 7." Gumm March c. 'r. GALLOWAY ,343,

MACHINEIOR CHAMFERING GEARS Filed March 16, 1940 7 Sheets-Sheet 5(Ittomeg March 7, 1944. c. T. GALLOWAY MACHINE FOR CHAMFERING GEARS 7Sheets-Sheet 4 Filed March 16, 1940 m M v n 3 W M m T.. a m R m Cattorney March 7, 1944. cqT. GALLOWAY MACHINE FOR GHAMFERING GEARS FiledMarch 16, 1940 '7 Sheets-Sheet 5 Fig 9 Inventor C'AHEE/VCE 7."GflLLOWflY arch 1944. c. 'r. GALLOWAY MAGHINE'FOR CHAMFERING GEARS FiledMarch 16, 1940 7 Sheets-Sheet 6- N wm llll'll 3nventor CLARENCE 7T'fizzawm I March 7, 1944.. ,c. "r. GALLOWAY 2,343,407

mcanm FOR CHAMFERING emns Filed March 16, 1940 7 Sheets-Sheet 7 290'Zinventbr F f y, 16 BB CLfiEEA/Cf 7". G/mowny attorney Patented Mar. 7,1944 MACHINE FOR CHAMFERING GEARS Clarence T. Galloway, Rochester, N.Y., assignor to Gleason Works, Rochester, N. Y., a corporation of NewYork Application March 16, 1940, Serial No. 324,347

17 Claims.

The present invention relates to machines for chamfering gears andparticularly to machines for chamfering straight bevel gears.

One object of the invention is to provide a chamfering machine whichwill be relatively simple in construction but extremely fast inoperation. To this end, a'further purpose of the invention is to providea machine on which all of the teeth of a gear may be chamferedsimultaneously by a single stroke of the work relative to the chamferingtool or tools.

Another object of the invention is to provide a chamfering machinehaving means for automatically feeding gears successively to operativeposition so that the chamfering operation may proceed with maximumefficiency and least possible lost time. To this end, it is also anobject of the invention to provide a machine having a turret forcarrying a plurality of gears, which may be rotated step by step tobring a new gear into operative position after each chamfering stroke.

Still another object of the invention is to Provide a machine havingmeans for indexing the work supporting turret automatically in time withthe mechanism for efiecting the ch'amfering operation so that chamferingand indexing may proceed in proper sequence without danger of damage tothe work or to the chamfering tools.

A still further object of the invention is to provide a hydraulicallyoperated chamfering machine in which the mechanism for rotating the worksupporting turret and the mechanism for effecting the chamferingoperation are interlocked.

.Other objects of the invention will be apparent hereinafter fromthespecification and from the recital of the appended claims when takenin som junction with the accompanying drawings.

In the drawings:

Fig. 1 is a front elevation, with parts broken away, of a chamferingmachine constructed according to a preferred embodiment of thisinvention;

Fig. 2 is a side elevation of this machine, parts being broken away;

Fig. 3 is a plan sectional view on 'a somewhat enlarged scale of thechamfering tools and tool holder, and showing diagrammatically therelation of the tools to a bevel gear which is to be chamfered;

Fig. 4 is a fragmentary vertical sectional view on a still furtherenlarged scale showing the tool support and associated parts and thelower end of the upper ram;

Fig. 5 is a bottom plan view of the upper ram;

Fig. 6 is a perspective view of one of the chamfering blades;

Fig. Tie a plan view of the work supportin turret and showing, brokenaway, part of the mechanism for actuating the same;

Fig. 8 is a fragmentary view showing the work supporting turret in planand the device for insuring that the gears, which are to be chamfered,have been positioned correctly in the turret;

Fig. 9 is a fragmentary sectional view on an enlarged scale on the line99 of Fig. 8, illustrating particularly the operation of the device forinsuring correct positioning of the work pieces;

Fig. 10 is a fragmentary developed View of the manually operable controlvalve for moving the lower ram to and from operative position and of thesleeve in which it rotates;

Fig. 11 is a sectionalview through the valve and sleeve, when the partsare in the position shown in Fig. 10, said section being taken in aplane corresponding to the plane II--l l of Fig. 10; Figs. 12, 13, 14.and 15 arecorresponding views taken in planes corresponding,respectively, to the planes I2l2, l3-l3, [4-44 and l5-l5 of Fig. 10; and

' Fig. 16 is a diagrammatic view showing the hydraulic circuit of themachine.

V The chamfering tool employed with the present invention has aplurality of internally projecting blades or teeth equal in number tothe tooth spaces of the straight bevel gear to be chamfered. The bladesor teeth of the chamfering tool are provided with side cutting edges andpreferably with top cutting edges also. The opposite side cutting edgesare shaped to be sub-,- stantially complementary to the opposite sidesof the teeth of the gear at the end of the teeth which is to bechamfered. The tool, in other words, has the general form of an internalgear which is axially coincident with the gear to be chamfered and whichis complementary to the gear at one end thereof. a

The chamfering operation is effected by passing the work through thechamfering tool. The side cutting edges of each chamfering blade thuschamber opposite sides of a tooth space of the gear and the top outingedge of a blade chamfers the bottoms of the tooth space. The chamferingcut is taken preferably toward thesmall end of the gear. The chamferingblades accordingly clear themselves, after taking their chamfering cuts,because of the taper of the gear.

chamfering tool is mounted below the plane of rotation of the turret andso positioned that when a work piece is at the cutting station, the workwill be above and in axial alignment with the tool.

At the cutting station there are two rams mounted in axial alignmentwith one another and with the cutting tool. The lower ram is adapted topass up through the chamfering tool so that its upper end may form aseat on which each work piece may rest when it reaches the cuttingstation. The upper ram carries at its lower end a center and a beveledgauging finger. The center is adapted to enter the bore of the gear,which is at the cutting station, when the ram is lowered, and the gaugefinger is adapted to enter a tooth space of this gear to position thegear precisely angularly so that its tooth spaces will be in registerwith the cutting teeth or blades of the tool.

"The two rams are actuated hydraulically. When a work piece reaches thecutting station, both rams are in their upper positions. When indexingof the turret has been completed and the gear that is to be chamfered isabove the cutting tool, the upper ram is lowered. This causes the-centerto enter the bore of the gear and-the gauge finger to enter a toothspace of the gear to bring the tooth spaces of the gear into accuratealignment with the teeth of the chamferin tool. As the upper ramcontinues its downward movement, the gear is clamped between the upperand lower rams. on the upper ram then forces the lower ram downwardlyalso, causing the gear to be forced downwardly through the blades of thefixed chamfering tool, thuscausing the sides and bottoms of its teeth tobe chamfered at one end.

When the chamfering has been completed, the lower ram will be moved ondownwardly away from the upper ram by. fluid pressure, causing the gear,which has been chamfered, to be stripped off of it by a series offingers and deflected into a chute which carries it away. The rams arethen returned to their upper positions and the work table is indexed tobring another gear to cutting position. The cycle then begins anew. j'On each downward stroke of the rams, a gear is chamfered and dischargedfrom the machine. At the end of the return strokes, a new gear isbrought into position to be chamfered. All that the operator is requiredto do is to keep putting gears on the work table at the loading station.

Reference will now be had to the drawings for a more detaileddescription of the invention. 20 denotes the base of the machine. Theupper face of this base is formed with a central recess or depressionwhich is adapted to receive a hardened plate or rest 22 (Figs. 1, 2 and4). On this plate or rest 22 there is mounted a seat member 3 which issecured in any suitable manner to the plate 22 against movement relativethereto. The seat member 23 is recessed to receive the tool Thecontinuous pressure head 24 which is keyed to the seat member 23 by akey 25 that holds the tool head 24 against rotation relative to the seatmember and locates the tool angularly on the seat member. Secured to thetool head by screws 26 is a tool block 21. The tool block 21 is providedon its under face with a plurality of radially disposed recesses inwhich are mounted the chamfering blades 30 (Figs. 3, 4 and 6).

The chamfering blades are adapted to rest upon the upper face of thetool head 24 and when the screws 26 are tightened up are clamped betweenthe tool block 21 and the head 24 so as to be rigidly held in place. Theplate 22, seat member 23, head 24, and block 21 are provided withaligned bores so that the upper and lower rams can pass through them aswill be described more fully hereinafter.

The machine illustrated in the drawings is ar ranged to chamfer thelarge ends of the teeth of straight bevel pinions P. The chamferingblades 30 are therefore provided with opposite side cutting edges 3| and32 (Fig. 6) which are complementary in profile shape to the profiles ofopp site sides 33 and 34, respectively, of the teeth 35 of the pinion atthe large end of the teeth. The chamfering blades may also be provided,as shown, with tip cutting edges 31 for chamfering the bottom lands 38of the pinion at the large ends thereof.

The chamfering blades are preferably relieved on their sides and tipsback of their upper or front faces. Thereby, the blades need only besharpened on their front faces, when they become dull, and the profileshapes of the blades will be retained throughout their useful life.After sharpening. of course, the blades are adjusted radially inwardlyto compensate for their change in height due to sharpening. For thepurpose of this inward radial adjustment, adjusting screws 40 may beprovided. These screws thread into the tool head 24 and have conicalupper ends which are adapted to engage against the beveled rear faces 42of the chamfering blades. There is one adjusting screw 40 provided foreach blade, although for the sake of simplicity only one screw is showninFig. 3 of the drawings. The screws are held in, any adjusted positionby lock-nuts 43.

The pinions, which are to be chamfered, are placed by the operator ofthe machine in openings 45 that are provided in a rotary table or turret46 (Figs. 2 and 7). The openings 45 are equi-spaced from one anotherangularly about the axis of the table or turret and are of a dimensionto readily receive the pinions. The pinions, when placed in theopenings, rest on the upper face of a plate 41 which is secured to theupper face of the base 20 of the machine beneath the table or turret.The table is secured by a screw 48 and a washer 49 to a shaft 50 whichis suitably joumaled in the base of the machine. The table is adapted tobe rotated intermittently by index mechanism, which will be describedlater, so as to move each pinion step by step from loading position tocutting position where it will register with the chamfering tool.

There is a gauge finger 52 (Figs. 4 and 7 secured at one side of eachopening 45 of the turret 46. These gauge fingers are secured to thetable or turret 46 by screws 53 and dowel-pins 54. The gauge fingershave tapered and beveled inner ends and each is adapted to enter a toothspace of a pinion which is placed in an opening 45 to roughly locate thepinion angularly in that opening.

As the turret is indexed around, the pinions are carried from theloading station to the cutting station, sliding over the top of theplate 41. The plate 41 is provided, however, with an opening 55 (Fig. 4)that registers with the bores of the plate 22, seat-member 23, tool head24 and tool block 21. This opening is larger in diameter than thediameter of the pinions P to be chamfered so that when each pinionarrives at the cutting station, it no longer rests on the plate 21. Itis then adapted to rest instead upon the upper end of a piston rod orram 60, which is adapted to pass up through these bores. To

prevent a pinion from cocking, however, as the table 46 in its rotationslides the pinion over the opening 55, a thin plate 6| (Fig. 4) may besecured in the opening 55. Thisplate 6| has internal teeth 62 (Fig. 7)roughly conforming to the shape of the tooth spaces of the pinions whichare to be chamfered.

The piston rod or ram 60 (Fig. 1) is adapted to slide through alignedopenings formed in a beveled nose 63, a guide member 64, and stuiiingbox65. The nose B3 is secured in any suitable manner to the guide member 64and the guide member 64 is secured in any suitable manner to a head 66.The head 65 is secured by screws 61 to the base 20 of the machine. Thestufling-bcx 65 closes the upper end of a cylinder I and is secured tothe head 66 and cylinder by screws II. The cylinder is mounted in acentral bore or opening I2 formed in the base 28.

The piston rod or ram 60 is secured to a piston I3 that is adapted toreciprocate in the cylinder 18. The piston I3 is secured against ashoulder, which is formed on the piston rod, by a nut I5 which threadsonto the lower end of the piston rod. The lower end of the cylinder Illis closed by an end plate 11 which is secured in position by screws I8.

The ram or piston rod 68, as already stated, is adapted to pass upwardlybetween the chamfering blades 38, through the aligned bores of the plate22, seat member 23, head 24, block 21, and plate 6I so that its upperend may form a rest for the pinion which is to be chamfered.

There is a column or upright 80 secured in any suitable manner to theupper face of the base 28. This column or upright is bored to form a Icylinder 8| which is in axial alignment withthe cylinder Iii. A piston82 is mounted in this cylinder to reciprocate therein and a piston rodor ram 83 is secured to this piston by a nut 84 which threads onto theupper end of the piston rod. The upper end of the cylinder 8| is closedby an end plate 85 which is secured to the column 80 by screws 86. Thepiston rod or ram 83 passes through a stufling-box 81 which closes thelower end of the cylinder BI and which is secured to the column 8!! byscrews 88. i

The lower end of the piston rod or ram 83 is formed with a reducedportion 90 (Figs. 4 and 5) which serves as a center and is adapted toenter the bore of a pinion which is to be chamfered to center thatpinion. There is a gauge finger 92 secured by a screw 93 and a dowel pin94 (Fig. 4) in a recess formed in one side of the ram 83. The lower endof this finger 92 is adapted to project beyond the end of the ram 83 soas to enter a tooth space of the pinion which is to be chamfered. Thefinger 92 has beveled sides so that it will readily enter a tooth spaceof a pinion. It is secured to the piston rod 83 in a definite angularrelationship to the chamfering blades 30 so that when the finger 92enters a tooth space IIiI of a pinion P, that tooth space will beaccurately aligned with one of thechamfering blades 30 and thereby allof the tooth spaces of the pinion will be aligned with the severalchamfering blades.

To guide the piston rod or ram 83in its movement there is .a collar 95secured to the projecting portion of the rod. This collar is secured inany suitable manner to an L-shaped arm '96. This arm is adapted to slidein an elongated guideway 91 that is formed in the front face of thecolumn 80.

Secured to the under face of the plate 22 is a plate I00 that carries aplurality of deflectors or fingers IIlI (Figs. land 2'). In thechamfering operation, a pinion .P is moved downwardly through thechamfering blades '30 by downward movement of the rams 83 and 68, aswill be described in more detail later, and the chamfered pinion iscarried on downwardly until it strikes the fingers or deflectors IflI.These serve to strip the pinion from the ram (GI) and deflect in onto achute IilZ down which it may slide into a suitable receptacle (notshown) placed at one side of the machine.

The ram 83 is moved upwardly again after the chamfering stroke until itclears the table it. The table is then indexed to bring another pinioninto position to be chamfered.

The table index mechanism is also hydraulically actuated. A cylinderIIfi (Fig. 7) is secured in a suitable bracket III that may be fastenedto or be integral with the base of the machine. A piston 'I I2 ismounted to reciprocate in a sleeve I I3 which has a pressed fit in thiscylinder. One end wall of the cylinder is closed by an end plate 4. Therod II5, which is integral with the piston H2, projects through astuffing-box H6 which closes the opposite end wall of the cylinder. Theprojecting end of the piston rod I I5 has'a threaded connection with arack I20 (Figs. '7 and 2) which slides in a suitable guideway formed inthe base of the machine.

This rack I 28 meshes with a spur gear segment I2I which is rotatablymounted on the same bushing I24 in which the shaft 50 is journaled;Fastened to the segment I2I by screws :22 is an. arm I23 and pivotallymounted on the outer end of this arm is a pawl I25.

The table 46 is formed on its periphery with a plurality of equi-spacednotches I26 which are adaptedto be engaged successively by the pawl I25.There is one notch for each work-receiving opening in the table. Duringchamfering, the piston H2 is in the position shown in Fig. 7 and thetable 46 is locked against rotafion by a lock-dog I28 which is alsoadapted to be engaged successively with the notches I 26 of the table.The lock-dog I28 is pivotally mounted at H2 in the bracket III. It isnormally held in looking position by a spring pressed plunger I30 whichslides in a lug I3I that is secured to the lraclret Hi. A coil springI82 which is housed in this lug and which surrounds the plunger servesto urge the plunger normally outwardly to hold the lock-dog I28 inlocking position. The plunger engages with a lug I33 formed integralwith the lock-dog.

'Pivotally mounted on the lock-dog I28 by means of a pin I34 is a tripdog I35. This trip dog is normally urged in a counter-clockwisedirect-ion about its pivot pin !34 by a spring is limited, however, byengagement of the tail of this dog with theblock I31. The pawl I25 isformed with an integral cam surface I 38.

To eifect indexing of the work table 46, the index mechanism is firstreset. This is effected by moving the piston II2 to the right from theposition shown in Fig. 7. On this movement, the arm I23 is rotatedcounterclockwise by the rack I20 and segment I2I and the pawl I25ratchets out of that notch I26 of the table 45 with which it has been inengagement and is carried on beyond the notch I26 of the table withwhich the locking dog I28 is in engagement. The table 4.6 is heldagainst rotation, however, during this movement, by the lock-dog I28. Asthe piston II2 moves on to the right,

the cam portion I38 of the pawl I25 comes into engagement with thetrip-dog I35 but merely rocks this trip dog in a clockwise directionabout its pivot pin I34 against the resistance of the spring pressedplunger I36.

The indexing operation is effected on the reverse movement of the pistonII2, that is, on movement of the piston to the left again. In thismovement the arm I23 is moved in a clockwise direction. The cam portionI38 of the pawl I25 again engages the trip-dog I35, but the tripdog isnow held against rotation by abutment of its tail against the lug I31.Thus the lockingdog I28 is caused to be lifted out of locking engagementwith the table 46. The pawl I25 then drops into that notch of the tablewith which the locking dog has previously been engaged. On the furtherleftward movement of the piston II2, then, the pawl I25 will rotate thetable 46 and index the same.

As the cam portion I38 of the pawl I25 rides clear of the trip dog I35,the locking dog I28 will drop back onto the periphery of the table underactuation of the plunger I30. When the table has been indexed far enoughfor the next notch I26 of the table to register with the locking dogI28, the locking dog will drop into this notch and lock the table upagain against rotation. The indexing of the table will thus have beencompleted and a new pinion brought into chamfering position.

To prevent indexing of the turret during chamfering or while the ram 83is in its downward position, the movements of the index piston H2 and ofthe ram pistons 13 and 82 are interlocked. The manner in which thisinterlocking is attained will now be described with particular referenceto the hydraulic diagram of Fig. 16.

The parts are shown in the position where the ram 82 is raised and theindexing operation of the table 46 is about to take place. The pressurefluid is pumped to the various parts from a pump I40 (Fig. 2) which issuitably mounted in the base of the machine and which is driven by amotor I 4 I. The pressure fluid flows through a line I42. The line I42is connected by a duct I43 with ports I44 of a sleeve I45 in which ismounted a reciprocable valve I46. The line I42 is also connected by aduct I41 with ports I48 of a sleeve I49 in which a valve I50 isreciprocably mounted.

With the valve I50 in the position shown in Fig. 16, the pressure fluidmay flow through the ports I48 of sleeve I49 into the ports I52 andthrough the line I53 to a valve I54, but this valve is normally heldclosed by a spring I 55 and the pressure from the line I53 serves onlyto seat the valve more securely. Hence, flow of the pressure fluid fromthe line I 53 is stopped at this point. The line I53 is connected,however, with a duct I56 which leads to the cylinder 10. The pressurefluid cannot flow, however, at this time from the duct I56 directly intothe cylinder 10 because this duct is closed by the piston 13 which is inits upper position. There is a short duct I51 connected with the ductI56 and leading to the upper end of the piston 13, but this duct isclosed by a ball check valve I58 which is pressed into position by aspring I59 and the pressure of the fluid in the line I51 serves only toseat the valve I58 the more securely. Hence at this time the pressurefluid is stopped from flowing from the line I56.

The pressure fluid may flow from the duct I43, however, through theports I44 of sleeve I45 and ports I60 of this sleeve into a duct I6 I.This duct connects with ports I62 in the lower end of a sleeve I63 inwhich a valve I 64 is reciprocably mounted. The pressure fluid thereforeserves to hold the valve I 63 upwardly in the position shown in Fig. 16.The ports I62 of the sleeve I 63 communicate through a duct I 65, whichis formed in the sleeve I63, with the ports I66 of this sleeve. Hence thpressure fluid may flow through the ports I66 and ports I61 into theline I68 which leads to the lower end of the cylinder I I0. Thus thepiston II2 will be forced from the position shown in Fig. 16 to theposition shown in Fig. 7, effecting indexing of the work table.

As the piston I I2 is thus moved in the cylinder IIO, the fluid on theopposite side of this piston is exhausted through the duct I10, andports HI and I12 of sleeve I63 into the line I13 which leads into a lineI14. This line I14 connects with the ports I 16 of a rotary valve I 15.The ports I16 are formed in a sleeve I18 in which the valve is rotatablyadjustable. During operation f the machine, the valve I15 occupies theposition shown in Fig. 16 and the ports I16 are connected by the groovesI19 of the valve with ports I that lead into a duct I 8| which leadsback to the sump of the machine.

The indexing movement of the piston H2 is dash-potted towards the end ofits stroke because the piston II2 will close off the duct I82 whichconnects with the duct I10 and thereafter further exhaust from thepiston is through the check-valve 255 and the duct I83. The duct I83connects with the duct I82.

When the piston I I2 has moved to the limit of its movement in thedescribed direction, it will clear the duct I84 in the side wall of thecylinder I I0 and the pressure fluid will now flow from the duct I68through the duct I 84 into the line I85 which leads to'the upper end ofthe cylinder 8 I. As a consequence, the piston 82 will be moveddownwardly in the cylinder 8I, thus moving the center and gauge finger92 into engagement with the pinion which is at the cutting station. Thiswill cause the pinion to be centered up and its tooth spaces to bebrought into alignment with the chamfering blades.

During the downward movement of the piston 82, the motive fluid exhaustsfrom the lower end of the cylinder 8I through the line I90. This linecommunicates with the duct I94 which is drilled in the valve block I92in which the valve I15 is mounted. The duct I94 leads to a ball checkvalve I98 which normally closes the opening between the duct I94 and aduct I99. The ball check valve is held normally closed by a coil spring200 whose tension may be adjusted by a nut 20I. This check valve servesto put some back pressure on the line I90 and insure smooth ee ie-e62operation of the piston 82 a it moves down-'- wardly. i The duct I99communicates with a line 205 that connects with the ports 206 of thesleeve I49. With the valve I50 in the position shown in Fig. 16, theexhaust fluid flows from the ports 26% through the ports 20'! of sleeveI49 into the line 208 which communicates with the line I14 that leadsback to the sump of the machine.

The cylinder I is closed to supply when it is in the position shown in-Fig. 16, as already described. Moreover, only restricted exhaust fromthe lower end of the cylinder is possible at this time. The duct 2 10which eommuhicet'es with the interior or the cylinder at the lower endthereof is normally closedby a spring pressed check valve 2| I. Hehce,the exhaust fluid can not flow from the lower end of the cylinder 10through the duct 2| 0 because thispassag'e is shut off. There is onlyone w-ayin which it may flow and that is through ducts 2I4 ofsmalldiameter' which are drilled in the" piston I3, as shown clearly inFigs. 1 and 16. Further'thanthi's, the exhaust fluid has to pass througha needle valve 2 I 5 which provides a still morerestricted-exhaustopening. When the piston I3 is in the upper positionshown in Fig; 16'; then, exhaust fluid from the lower end of thecylinder can only escape through the needle'v'alve 2I5. Thence it mayflow through th line 2I8, the ports 2| 9 of sleeve I18, groove 22I ofvalve I 'I5,and ports'22'0 flow through line 205; ports 206 and-201 ofsleeve M9 and duct 208' into duct l'l4whehce it' l'nay flow back to thesump.

After the center 90 and gauge finger 92 have engaged the pinionwhichisat the cutting station, the ram 83' will continue to descend bypressure of the motive fluid'on-the upper end of the piston 82. Thepinionwill thus be clainped between the upper ram 83 and lower ram 60;The

through the chamfering blades 30 and will be chamfered.

When the lower ram I3- has descended far-- enough for the ports 2I6 and2H in theside wall of cylinder I0 to be exposed, the fexhaust'fiuid inthe lower'pa'rt of the cylinder") may exhaust more freely into the duct2'I0, thus allowing more rapid downward movement'o fthe ram 60. Thisoccurs after the chamfering has been ecchm plished and at a time whentheram 83has very nearly reached-the limit of its downward move ment. a

At about this same time, the piston l 3will have descended far enoughfor the duct 225 leadinginto the cylinder I0 to be uncovered. Thenthepressure fluidflowing fro'm'theline I56 exerts its influence on thepiston and moves it rapidly downward away from the'ram 813. This servesto move the rain 60 downwardly far en oughio'r the pinion to be strippedfrom the head ofthis'ram by the fingers II 80 that it tens intoth'ebhilt'e I62 and is carried away from-the-machine;

While this is occurring, the ram 82 will have moved far enough so thatthe piston uncovers the duct 22'! leading into the cylinder 8I. Thepressure fluid flowing into-the upper endbf' the,

cylinder 8I then passesput through the duct 22'! and through the ports228 or the sleeveinto the bottom of the valve 146;] This causes thevalve I46 to he moved upwardly rromthe position shown Fig. 16. Thepressure fluid, which has been flowing from the line I43, is thuscausedto now through the orts I44 and zao ntothe line 231, whence itnews through the ports 232 of the sleeve I49 to the upper end or thevalve I50, fercing that valve downwardly from the position shown in Fig.16. A

The shifting of this valve I56 causes a reversal of the direction of newofpressiure fluid to the cylinder 10. The pressure fluid flowing fromthe line I41 is now caused to now through. the ducts I48 and 206 intothe line 205, whence it flows through the duct I99, port's 220 of sleeveI18, grooves 22: of valve I15,-ports 219 of sleeve I16 and duct 2I6 tothe" duct ZIO' in the side wall of the cylinder I0. Thus the check valve2II is forced open and the pressure fluid enters the bottom of thecylinder 10. At the same time the ducts I57 and 225 in the upper end ofthe cylindei" 10' are put 'on exhaust through the line I56, ports I52and 246' of sleeve I49,ducts 241, 208 and I74. Thus the piston 13 ismoved upwardly again in the cylinder I0.

During the upward movement of the valve I46, as described, the motivefluid is exhausted from th'eupper end or this valve through the ports235, the ducts 236,256 and 231, and the check valve 238'into the line239' which leadsto the sump. Theche'ck valve238'serv'es to exert'sufficient back pressure to insure smooth operation of the apparatus. 7I

As the valve I moves deivhwardly, as described, the motive fiuidi'sexhausted from the lower end of this valvethrough the ports 240, theduct 24'I, thepor'ts I62 of sleeve I63, and either through the duct I65of this sleeve, the ports I66 and I6! of thissle'e've and the line I13back tothe sump, or through theports I62, line I6I,-

ports I60 and 243 of sleeve I45 and'line' 244 into theline I14 whichgoes back to the sump.

When the; valve I50 is moved to its lower position; asde'scribed, notonly does the pressure fluid fiOW'thIOllgh the 1in2li5, dllt I99, andline 218 through the'line I85, the duct-.249, check-valve I54; duct I53,ports I52 and 246 of sleeve I49 and lines 208 andII4 baokto the sump.

Towards the end of t e described upward" travel of the piston", thispiston shuts off the duct 225 and thereafter the motive fluid mustexhaustthrough the ball check valve I58; Thereby the speed of upwardmovement-of the piston I13 isre'tarded to prevent shofck when' thepiston bot= tent-Sm the upper end or theeynhae -n; y

when the piston 82 has been moved upwar ly far; enough, it uncovers theline-248'; thus permit.-

tingthe pressure fluid to flow-from; the line. I

upperend ofjhe-sleeve I53 tpii'qicethe' valve I64 downwardly-froin thepositioh "sh'OWh' ih Fig'.f

from the'line 248 through the ductizsz; which is. cut in t e s etithe-sleeve; I63; ariajthe ports. 25s and met this' 'sleeve 'inte thline no. Thenceit flows t roughjthecheers/awe zss nto' the upper end orthe cylinder no te force" the piston II2 downwardly. Thus the piston H2is moved back to the right from the position shown in Fig. 7 to resetthe index mechanism. As the piston so moves, it uncovers the duct I82permitting faster flow of the motive fluid into the cylinder II8 so asto achieve accelerated movement of the piston. During the describedmovement, the motive fluid exhausts from the opposite end of thecylinder IIII through the duct I68, the ports I61 and In of the sleeveI63, and the duct I13 into the line I14 which leads back to the sump.

When the piston II2 has moved far enough to uncover the duct 256, thepressure fluid flows from the duct I82 through the duct 256 into theline 236. Thence it flows through the ports 235 in the upper end of thesleeve I45 to return the valve I46 to the position shown in Fig. 16.This puts the line I6I back on supply from the line I43 and causes thevalve I64 to be returned to the position shown in Fig. 16. At the sametime, it causes the line 24I to be put on supply from the line I 6|through the ports I62, causing the valve I58 to be returned to theposition shown in Fig. 16. The pressure fluid now flows from the lineI6I through the duct I65, and ports I66 and I6! of the sleeve I63 intothe line I68. Thence it enters the right hand end of the cylinder I In(Fig. 7) to move the piston to the left in Fig. 7 and effect theindexing operation again. Thus is initiated the new cycle.

So the operation proceeds. First the work table 46 is indexed bymovement of the piston II2 to bring a new pinion into chamferingposition. At the end of the movement of this piston the port I84 isuncovered and pressure fluid is supplied through the line I85 to theupper end of the cylinder 8I causing the ram 83 to descend. The center98 and finger 92 then engage the pinion and center and locate it. Thecontinued descent of the ram 83 causes the pinion to be clamped betweenthe two rams 83 and 68 and the pinion and lower ram 68 are carrieddownwardly and the pinion is forced through the chamfering blades tochamfer it. The descent of the ram 68 then causes the port 225 to beuncovered and the pressure fluid is then applied to the upper end of thpiston I3 from the line I56. This causes the ram 68 withthe pinionresting on it, to be carried rapidly away from the ram 83. As thedescending ram 68 moves through the fingers I8I, the now chamferedpinion is stripped off the ram by the fingers. While this is occurring,the ram.82 will have moved far enough downwardly so that the piston 82uncovers the duct 221. This allows the pressure fluid to flow from theline I85 into the line 221, causing the valves I46 and I58 to be shiftedupwardly and downwardly, respectively, from the positions shown in Fig.16. This causes reversal of the direction of flow of the pressure fluidto the cylinder 10. It also causes reversal of the direction of flow ofthe pressure fluid to the cylinder 8I. Thus the two rams are movedupwardly again. When they have returned to their upper positions, theline 248 is uncovered and the pressure fluid now flows from the line I98into the line 248. This causes the valve I64 to be moved downwardly fromthe position shown in Fig. 16 and the line I18 to be put on supply. Thusthe piston I I2 is moved to the right (Fig. '7) and the index mechanismis reset. When the piston II2 has moved far enough to uncover the duct256, then the pressure fluid flows from the line I'IO into line 236.This causes valve I46 to be shifted back to the position shown in Fig.16,

causing the valves I64 and I58 to be returned to the positions shown inFig. 16 also. This reverses the direction of flow of the pressure fluidto the cylinder H8 and the piston H2 is moved to the left (Fig. 7) inthe cylinder II8, indexing the work table to bring a new pinion to thecutting station and an empty opening 45 to the loading station. Theoperator then puts a new pinion in the opening 45.

To insure that the operator places the pinions in the openings 45 of thetable 46 with the smallends up, a detector device is provided. Thiscomprises an arm 268 (Figs. 8 and 9) which is pivotally mounted by meansof a pin 26! on a bracket 262 that is secured to the base 28 of themachine at one side of the table. This arm 268 is long enough to projectover the table 46. An adjustable screw 263 is threaded into the base 28of the machine and the head of this screw is adapted to contact with theunder face of th arm 268 so as to hold the arm horizontal with its underface just clearing correctly positioned pinions as the work table isindexed. A pin 265 that has a conical head 266 is secured in the plate41. The back face of a pinion P that is positioned in the table 46 withits small end up will clear the head 266 of the pinion 265, as shown infull lines in Fig. 9, but if the operator makes a mistake and puts apinion in an opening 45 of the table 46 with the small end down, thenthe head 266 of the pin 265 will contact the pinion when the pinion ismoved over the pin by indexing of the table. This will cause the pinionto project up far enough, as shown in dotted lines at P in Fig. 9, toengage the arm 268 and lift this arm upwardly about its pivot pin 26I. Alimit switch 268 is mounted on the plate 28 so that its plunger 269 isadapted to engage the under face of the arm 268. This is a normally openlimit switch and is Wired into the starting circuit of the pump drivemotor I4I (Fig. 2). As long as the arm 268 is horizontal, the limitswitch is held closed so that the circuit to the motor MI is maintained,but if the arm is lifted upwardly by an inverted pinion, then the limitswitch is allowed to open, breaking the circuit to the motor andstopping the operation of the machine. Thus, damage, which might arisein an attempt to chamfer an inverted pinion, is prevented. The arm 268may be beveled at one side, as indicated at 261, so that it will ride upgradually if a pinion has been put in the table inverted.

It will be noted, from Fig. 1, that the top surfaces of the guide member64 and of the head 66 are inclined downwardly toward one side of themachine. This is for the purpose of allowing the chips produced in thechamfering operation to fall toward this side of the machine onto ashelf 218, where they may be raked out by a suitable tool insertedthrough the opening 2'" in the side of the machine. Chips falling off ofthe shelf 218 drop onto the shelf 272 and can be raked oif by insertionof a suitable tool through the opening 213 in the base of the machine.

A suitable coolant may be supplied to the points of the cutting blades38 through a duct 215 (Fig. 4) which communicates with a peripheralgrove 216 out in the tool block 21. Ducts 2'" lead from this groove tothe tip of each of the cutting blades. The coolant may be supplied froma pump mounted at any suitable point in the base of the machine anddriven in any suitable manner, and it may be in suflicient quantity notonly to keep the points of the wam blades cool but alsoto wash the chipsoff of them.

Reference has already been made to' the manually operable valve I15.This valve occupies the position shown in Figs. 10 to 16 duringoperation of the machine. In the position of the valve shown in thesefigures, the grooves I19 in the valve connect the ports I16 and I88 ofthe valve sleeve I18, while the grooves 22l of the valve connect theports 2I9 and 228 of the sleeve I18.

The valve body I15 is also provided with two diametrically opposedgrooves 288 which are somewhat elongated as compared with the grooves22I and I19 and which are displaced angularly about the valve body withreference to the grooves I19 and 22I. The valve body is further providedwith diametrically opposed grooves 282 which are in longitudinalalignment with the grooves I19 and 22I. Besides the ports 228, there aretwo ports 283 formed in the sleeve I18 in the same plane as the ports228and diametrically opposed to one another. Spaced longitudinally fromthese are two diametrically opposed ports 284. These ports .are somewhatslightly displaced angularly from the ports 283. Spacedlongitudinallyfrom the ports 284 are ports 285 which are also displacedsomewhat angularly from the ports 284. Spaced longitudinally from theports 285 but in angular alignment therewith are two diametricallyopposed ports 286.

The valve is adapted to be rotated by a knob 298 (Fig. 16) which issecured to an arm 29I that is pinned to the stem 292 of the valve. Aspring pressed detent 294 which engages in notches in a, plate 295 thatis secured to the valve housing, serves to hold the valve in anymanually adjusted position.

As already described, the valve is shown in Fig. 16 and in Figs. 10 to15 inclusive in the position which it occupies when the machine is inoperation. When it is desired to remove the cutter from the machine,however, as for sharpening, it is necessary to move the ram 68downwardly until the piston 13 bottoms in the cylinder 18. This is donewhen the piston 13 is at the lower limit of its normal working range inthe cycle of operation of the machine. For this purpose,the operatorrotates the valve I15. The

grooves I19 of the valve body are thus moved out of registry with theports I88and I16 of the sleeve I18, closing off the connection betweenthe lines I14 and I8I. At the same time, the grooves 22I are moved outof registry with the ports 2I8 and 228 closing off the connectionbetween the line 2I8 that leads to the bottom of the cylinder 18 and theline 285. At the same time, also, the grooves 288 will have moved intoposition to connect the ports 284 and 285. Thus the line 298 which leadsto the upper end of the cylinder 18 is temporarily connected with theline 29L This latter line communicates with the line I8! thatleads tothe sump of the machine. In the further movement backward of the handle298, however, the groove 288 in the valvebody is moved 'far enough toconnect the ports 283 and the ports 284 and thegroove 282 is moved farenough to connect the ports 285 and the ports 288. When the piston 13 isat the lower limit of its normal working range, the valve I58 (Fig. 16)is in its downward position.

Hence, when'the valve I15 is in position to connect the ports 285 and286, the upper end of the cylinder 18 will be put on supply'from theline 285 through the ports 283, grooves .288, ports teeth of other typesof gears also.

284 and line 298, while the lower end of the'cylinder 18 will be put onexhaust through the line 293, the ports 286, the grooves 282, the ports285 and the line 29I which leads to the sump. Thus the piston 13 will bemoved completely downward until it bottoms in the cylinder 18.

When the tool has been removed and a new tool inserted in the machine,the operator swings the handle 298 in the reverse direction so that thegrooves 288 are moved out of registry with the ports 283 and are movedinto registry with the ports 285 to connect the ports 284 and 285. Thisputs the upper end of the cylinder 18 on exhaust through the line 298,ports 284, grooves 288, ports 285, line 29I, and line I8I. At the sametime, the grooves 282 move out of registry with the ports 285 and 286 toclose the line 293 leading from thebottom of the cylinder 18. In thefurther movement of the valve I15 to operative position, the grooves I19are returned into registry with the ports I88 and I16, and-the grooves22I are returned into registry with the ports 2I8 and 228 to theposition shown in Figs. 10 to 16 inclusive. Thus the lines 2I8 and I98leading to the lower ends of the cylinders 18 and 8| are put back onsupply and the pistons 13 and 82 are moved upwardly causing the machineto resume its normal operative functions. 7

While the invention has been described par- .ticularly in connectionwith the chamfering of the-teeth of straight bevel gears, it will beobvious that it may be applied to the chamfering of the it may be saidthat while the invention has been illustrated in connection with aparticular embodiment thereof, it is capable of still furthermodification, and this application is intended to cover any variations,uses, or adaptations of the invention, following, in general, theprinciples of "the invention and including such departures from thepresent disclosure as come within known or customary practice in the artto which the invention pertains and as may be applied to the essentialfeatures hereinbefore set forth and as fall within the scope of theinvention or the limits of the appended claims.

Having thus described my invention, what I claim is:

1. A'machine for chamfering gears comprising a tool having a pluralityof cutting blades equal in number to the tooth spaces of the gear to bechamfered and arranged radially of a common axis, a work support adaptedto hold the gear so that its axis is in alignment with the axis of thetool, means for reciprocating the work sup- .port to pass the teeth ofthe gear through the cutting blades ofthe tool, and relatively fixedmeans arranged beyond the tool and operable cutting blades arrangedradially of a common axis, an upper and a lower ram mounted toreciprocate along said common axis, means for reciprocating said rams,and means for controlling their reciprocating movements so that they arefirst moved toward one another to efiect clamping of the gear, then aremoved in one direction to pass the teeth of the gear across the tool,are then separated to permit removal of the'chamfered gear, and are thenreturned to starting position.

I .3. 'A machine .forchamfering gears comprising In general a relativelystationary tool having a plurality of cutting blades arranged radiallyof a common axis, an upper and a lower ram mounted to reciprocate alongsaid common axis,'means for reciprocating the rams, means forcontrolling the movements of the rams so that'they are first movedtoward one another to clamp a gear between them, then are moved in onedirection to pass the teeth of the gear through the cutting blades ofthe tool, are then separated and the lower ram is moved on further inthe described direction, and are then reversed to return to originalpositions, and means operative during the extended movement of the lowerram to strip the chamfered gear from the lower ram.

4. A machine for chamfering gears comprising a base, a relativelystationary tool mounted in the base, an upper ram and a lower rammounted in alignment for reciprocation in the base, means forreciprocating the upper ram, means for reciprocating the lower ram,means for timing the two reciprocating movements so that the upper ramfirst moves towards the lower ram to effect clamping of a gear betweenthem, then the continued movement of the upper ram causes the gear andthe lower ram to be moved in the direction of movement of the upper ramto pass the teeth of the gear across the tool to effect chamfering, thenthe lower ram and gear are moved away from the upper ram a predetermineddistance, and then both rams are returned to their initial positions,and means for stripping the chamfered gear from the lower ram when thelower ram moves away from the upper ram.

5. A machine for chamfering gears comprising a base, a relativelystationary tool mounted in the base, an upper ram and a lower ram,hydraulically operated means for reciprocating the two rams, valve-meansfor controlling the movements of the two rams so that pressure is firstapplied to the upper ram to move it in one direction to clamp a gearbetween the two rams and the gear and lower ram are then moved by theupper ram to pass the gear across the tool, then pressure is applied tothe lower ram to move it away from the upper ram, and then the directionof flow of the pressure fluid to the two rams is reversed to return bothto starting position, and means for stripping a chamfered gear from thelower ram when the lower ram moves away from the upper ram.

6. A machine for chamfering gears comprising a base, a work support, atool support, a tool mounted on the tool support having a plurality ofcutting blades which are arranged radially of a common axis and haveside cutting edges complementary to the sides of the gear to bechamfered, means for effecting relative reciprocating movements betweenthe tool and work support along the axis of the tool to effect thechamfering operation, a work holder rotatably mounted on the base andadapted to hold a plurality of gears, and means for indexing the workholder once for each relative reciprocation of the tool and work supportto bring a new gear to the work support for chamfering.

7. A machine for chamfering gears comprising a base, a work holderrotatably mounted on the base and adapted to hold a plurality of gears,means for indexing the work holder to move the gears step by step from aloading station to a cutting station, a cutting tool mounted at thecutting station having a plurality of cutting blades which are arrangedradially of a common axis and which have side cutting edgesapproximately complementary in profile shape to the sides of the teethof the gear to be chamfered, means for effecting a relativereciprocatory movement between th cutting tool and a gear, when the gearreaches the cutting station, to efiect chamfering of the gear, and meansfor actuating the index mechanism, after each relative reciprocatorymovement, to bring a new gear to the cutting station.

8. A machine for chamfering gears comprising a base, a work holderrotatably mounted on the base and adapted to hold a plurality of gears.means for indexing the work holder to move gears step by step from aloading station to a cutting station, a cutting tool mounted at thecutting station having a plurality of cutting blades which are arrangedradially of a common axis and. which have side cutting edgesapproximately complementary in shape to the sides of the gear to bechamfered, a work support to which a gear is transferred by the movementof the work holder when the gear reaches the cutting station, means forprecisely positioning the gear on the work support at the cuttingstation, and means for reciprocating the work support relative to thetool to effect chamfering.

9. A machine for chamfering gears comprising a base, a cutting toolmounted on the base, a stripping member mounted on the base, a worktable rotatably mounted on the base and having a plurality of openingstherein to hold a plurality of gears, means for indexing the work tableto move gears step by step from a loading station to the cuttingstation, a work support reciprocably mounted in the base and positionedto receive a gear when it reaches the cutting station, a positioningmember mounted on the base to be in alignment with the work support,means for reciprocating said positioning member, and means forcontrolling the movements of the positioning member and work support sothat the positioning member is moved down through that opening of thework table, which is at the cutting station at a given time, to clamp aear on the work support and to move the work support downwardly to passthe gear across the cutting tool and past the stripping member, and thenreturn the work support and the positioning member to initial position,and means for indexing the work table when the positioning member hasreturned to initial position clear of the table.

10. A machine for chamfering gears comprising a base, a cutting toolmounted on the base having a plurality of cutting blades arrangedradially of a common axis and having side cutting edges approximatelycomplementary in shape to sides of the teeth of the gears to bechamfered, a work holder rotatably mounted on the base and adapted tocarry a plurality of gears, means for indexing the work holderperiodically to move gears step by step from a loading station to acutting station, reciprocable means for moving a gear, when it reachesthe cutting station, past the cutting tool to effect chamfering of itsteeth, means operative after each reciprocating movement is completed,to actuate the indexing means, and means operative after each indexingoperation is completed, to actuate the reciprocable means.

11. A machine for chamfering gears comprising a cutting tool, a workholder adapted to carry a plurality of gears, means for indexing thework holder to move gears step by step from a loading to a cuttingstation, a cutting tool at the cutting station, means for effecting arelative movement.

between the cutting tool and the gear at the cutting station to chamferthe teeth of the gear, a stationary member mounted beneath the workholder in such position as to engage one end of a gear carried by thework holder if the gear is incorrectly positioned on the work holder andto move said gear outwardly, a movable contact member mounted at theopposite side of the work holder in position to engage the opposite endof any gear so moved outwardly, and means operable, when said contactmember engages a gear, to stop the operation of the machine.

12. A machine for chamfering gears comprising a base, a tool supportfixedly mounted in the base, a tool mounted on said support and having aplurality of cutting blades arranged radially of a common axis andhaving side cutting edges approximately complementary to teeth of thegear to be chamfered, a work support mounted on said base forreciprocation along said common axis, and a positioning member alsomounted on said base for reciprocation along said common axis andprovided with a center adapted to enter the bore of a gear to bechamfered and with a finger adapted to enter a tooth space of the gearto locate the gear correctly on the work support, means for actuatingsaid positioning member to effect location of the gear, and means forthereafter actuating the work support to pass the gear across the toolto chamfer its teeth.

13. In a gear cutting machine, a tool, a rotary work holder havin aplurality of work-receiving openings, a finger arranged at eachwork-receiving opening to enter a tooth space of a gear blank that ispositioned in said opening to position the gear blank roughly in theopening, means for indexing the work holder to move work piecessuccessively from a loading station to a cutting station, and meansarranged at the cutting station to position a gear blank precisely ineach opening, and means for automatically bringing the last named meansinto operative engagement with each gear blank when the gear blank isindexed to the cutting station.

14. In a gear cutting machine, a tool, a rotary work holder having aplurality of Work-receiving openings, a finger arranged at eachWork-receiving opening to enter a tooth space of the gear blank that ispositioned in said opening to position the gear blank roughly in theopening, means for indexing the work holder to move the gear blankssuccessively from a loading station to a cutting station, a ram memberhaving a center formed thereon adapted to enter the bores of the gearblanks, a finger secured to said ram member and adapted to enter a toothspace of a gear blank, and means for automatically actuating said ram tomove the center and th last-named finger into engagement with a gearblank to position the blank precisely in an opening of the work holderwhen the blank reaches the cutting station.

15. In a gear cutting machine, a base, a work holder rotatably mountedon the base and provided with a plurality of openings adapted to receivea plurality of gear blanks, a stationary plate disposed beneath saidwork holder to prevent work pieces from dropping through said openings,means for indexing the work holder to move the work pieces successivelyfrom a loading to a cutting station, said plate having an openingtherein at the cutting station of suflicient siz to permit a gear blankto pass freely therethrough, and means aligned with the opening in theplate to support a gear blank during the cutting thereof.

16. In a gear cutting machine, a base, a work holder rotatably mountedon the base and provided with a plurality of openings adapted to receivea plurality of gear blanks, a stationary plate disposed beneath saidwork holder to prevent work pieces from dropping through said openings,means for indexing the work holder to move gear blanks successively froma loading to a cutting station, said plate having an opening therein atthe cutting station of sufilcient size to permit a gear blank to passfreely therethrough, means aligned with said opening to support a gearblank during the cutting thereof, said last named means beingreciprocable, a tool mounted in stationary position beneath the openingin said plate, and a reciprocable ram for forcing the gear blank, whichis at the cutting station, and said supporting means downwardly to passthe gear-blank by the tool,

17. In a gear cutting machine, a rotary work holder adapted to carry aplurality of gear blanks, means for indexing the work holder to move theblanks successively from a loading station to a cutting station, amember mounted on a relatively fixed part of the machine to engage eachwork piece as the work holder is rotated and adapted to move a blankoutwardly if it is incorrectly positioned'in the work holder, a movablemember arranged above said work holder in position to contact with andbe moved by any blank that is moved outwardly, and means operable onmovement of the last named member to stop the machine.

CLARENCE 'I. GALIJOWAAY.

